MUC1 and neoplasm: Given that SCLC can be classified into four subtypes (SCLC‐A, SCLC‐N, SCLC‐P, and SCLC‐I) based on gene expression profiles.[2, 39] To further explore MUC1 expression in SCLC subtypes, we analyzed single‐cell RNA sequencing data from tumor tissues and found that MUC1 was prominently expressed in SCLC‐A and SCLC‐N subtype cells (Figure 1E–G and Table 2).